Fuel cell power systems convert a fuel and an oxidant to electricity. One type of fuel cell power system employs a proton exchange membrane (hereinafter “PEM”) to catalytically facilitate reaction of the fuel (such as hydrogen) and the oxidant (such as air or oxygen) to generate electricity. Water is a byproduct of the electrochemical reaction. Typically, fuel cell components such as plates include port holes that permit reactants and water to flow into tunnel regions, past seals, and into exhaust manifolds. Fuel cell components such as subgaskets also have boundaries past which reactants and water flow in route to the exhaust manifolds. However, where the port holes and the boundaries have squared (approximately 90°) edges, surface tension pins water droplets and inhibit a rapid removal of water. An accumulation of water within the fuel cell must be managed in order to optimize a performance of the fuel cell.
A number of strategies are known for removing water from the tunnel regions of the fuel cell. One strategy is described in Assignee's co-pending U.S. Pat. Appl. Pub. No. 2008/0171253 to Owejan et al., the entire disclosure of which is herein incorporated herein by reference. Owejan et al. describes a bipolar plate for a fuel cell having an exhaust opening with a chamfered peripheral edge in communication with an active surface of the fuel cell, and forming a water removal channel.
Another strategy is described in Assignee's co-pending U.S. Pat. Appl. Publ. No. 2008/0118809 to Tighe et al., the entire disclosure of which is hereby incorporated herein by reference. Tighe et al. describes a fuel cell stack having a porous material internally disposed in the fuel cell stack outlet manifolds to facilitate a transport of liquid water from fuel cell plate outlets.
A further strategy is described in Assignee's co-pending U.S. patent application Ser. No. 12/244,992 to Owejan et al., the entire disclosure of which is
A further strategy is described in Assignee's co-pending U.S. patent application Ser. No. 12/244,992 to Owejan et al., the entire disclosure of which is hereby incorporated herein by reference. U.S. patent application Ser. No. 12/244,992 describes a conduit having a continuous seam formed between a first plate and a second plate of a bipolar plate to facilitate a transport of water to an outlet of a fuel cell having the bipolar plate.
As described in U.S. Pat. No. 6,936,369 to Komura et al., it is also known to use a porous, water-absorbing tube to discharge water to the outside of a fuel cell stack. The entire disclosure of Komura et al. is hereby incorporated herein by reference.
There is a continuing need for cost effective fuel cell components such as fuel cell plates, which facilitate a transport of water through the fuel cell. Desirably, the features of the fuel cell components facilitating the water transport are inexpensive, minimize the number of required components, and are simple to manufacture.